Purpose: In this study, essential oil (EO) compositions of the dried and fresh aerial parts of Origanum majorana cultivated in the research field and collected from f from Mersin was investigated. Material and Methods: EO was distilled by using Clevenger type apparatus for 3 h and the chemical compositions were detected in GC-MS. While, the oil yields of the the collected marjoram was determined to be 2,5 ml both in dried and fresh aerial parts, the yields of the cultivated plants for fresh and dried parts were 3.6 ml and 5 ml, respectively. The cultivation of the plant had positive effects on the EO yield. Drying of the material also increased the oil yield in the cultivated marjoram. Results: While there were 42 and 35 of EO components were observed in the fresh and dried parts of the collected marjoram, respectively; in the cultivated plants there were 30 and 40 components detected. Besides EO yields, in this research the differences with respect to composition and components were determined between the cultivated and collected plants. On the other hand, in this study, it was determined that the EO compositions varied with respect to be fresh or dry of the plant parts. It was observed that carvacrol and linalool were the major EO contents. Conclusion: The aim of the study to compare of differences between the EO compounds and compositions varied according to be the plant fresh or dry and collected or cultivated.